Batteries have taken over the NEM's most valuable hours. During the evening peak, BESS now sets the wholesale price more often than any other technology, in every mainland state. Coal, gas and hydro have all been displaced from the role they used to play. This is the first clear sign that the battery fleet is structurally setting peak prices, not just trading around them, and the mechanism behind it explains why revenues have fallen as installed capacity surged at the end of 2025.

In March 2026, batteries set the price in 46% of intervals between 5-9pm across the NEM , up from 16% a year earlier. And in the mainland states, the share was even higher. BESS passed 60% in NSW and Queensland, and topped 50% in Victoria and South Australia. The next-highest technology in each state sits below 20%.

Batteries are setting prices more frequently because new capacity bought online in the late-2025 wave brought is bidding actively into the evening peak, rather than waiting for prices to spike. That capacity now sits between coal and gas in the supply stack, pushing prices to frequently clear against battery bids. Evening peak prices now settle at a median of $88/MWh with a top 10th percentile of $132/MWh, firmly inside the battery bid range.

Key takeaways

• BESS in March set the NEM evening peak price 46% of the time, up from 16% a year ago. The technology is now the dominant price-setter in every mainland state.
• The fleet added 2.4 GW of bid capacity priced less than $300/MWh year-on-year, mostly in a four-month wave at the end of 2025.
• New sites coming online bid 85 to 99% of peak capacity below $300/MWh; older short-duration sites still hold 70 to 95% above $300.
• When BESS is marginal in the peak, the premium it sets above coal has halved from $50/MWh to $19/MWh.

How has BESS has shifted the bid stack?

Of the 3.6 GW added in 2025, 2.2 GW came online between October and the end of the year. Queensland captured more than half of this through Western Downs 2, Brendale, Ulinda Park, Tarong and Supernode 1. Meanwhile, New South Wales added the single largest unit in Eraring.

Most of this capacity entered the NEM bidding in the $0 to $300/MWh range. This is what has driven the increase in BESS price setting in the evening window: there is now a meaningful volume of BESS bids inside the typical clearing-price band.